Itaconamic acids



United States Patent Office 33,173,945 Patented Mar. 16, 1965 3,173,945TTACGNAMIC ACIDS Harry J. Andress, Ira, Pittman, and Paul Y. C. Gee,Woodbury, N.J., assignors to Socony hiobil Gil Company, Inc, acorporation of New York No Drawing. ()riginal application Oct. 6, H58,Ser. No. 765,296, now Patent No. 3,046,1li2, dated July 24, 1962.Divided and this application st. 24, 1961, Ser. No. 147,175

Claims. (Cl. zed-5m This invention relates to the improvement ofnon-lubricating pretroleum fractions. It is more particularly concernedwith distillate fuel oils containing during prolonged storage periods,to prevent screen-clogging, and to prevent rusting of ferrous metalsurfaces.

It is well known that fuel oils are prone to form sludge or sedimentduring periods of prolonged storage. This sediment, of course, has anadverse effect on burner operation, because it has a tendency to clogscreens and nozzles. In addition to sediment formed during storage, mostfuel oils contain other impurities, such as rust, dirt, and entrainedwater. The sediment and impurities tend to settle out on equipmentparts, such as nozzles, screens, filters, etc, thereby clogging them andcausing the equipment to fail.

A further factor, incident to the storage and handling of fuel oils, isthe breathing of storage vessels. This results in the accumulation ofconsiderable amounts of water in the tanks, which presents a problem ofrusting in the tanks. Then, when the oil is removed for transportation,sufiicient water may be carried along to cause rusting of ferrous metalsurfaces in pipelines, tankers, and the like.

Generally, it has been the practice to overcome the aforedescribeddifficulties with a separate additive for each purpose, i.e., with asediment inhibitor, an antiscreen clogging agent, and an antirust agent.The use 'of several additives, however, gives rise to problems ofadditive compatibility, thus restricting the choice of additivecombinations. In addition, of course, the use of a plurality ofadditives unduly increases the cost of the fuel. It has been proposed toovercome two difiiculties, e.g., sedimentation and screen clogging, withone additive. Insofar as is known, however, few single addition agentshave been found effective against sedimentation, screen and nozzleclogging, and rusting of ferrous metal surfaces.

It has now been found that all three problems, i.e., sedimentation,screen clogging, and rusting, can be solved by the use of a single fueloil addition agent. It has been discovered that a distillate fuel oilcontaining minor amounts of certain amic acids and amine salts thereofis effectively inhibited, simultaneously, against all threeaforementioned ditficulties.

Accordingly, it is a broad object of this invention to provide a fueloil having properties improved with a minimum number of addition agents.Another object is to provide a fuel oil having a single additive adaptedto inhibit sedimentation, to prevent screen clogging, and to preventrusting of ferrous metal surfaces with which it comes in contact. Aspecific object is to provide certain novel amic acids or amine saltsthereof and fuel oils containing them. Other objects and advantages ofthis invention will become apparent to those skilled in the art from thefollowing detailed description.

The present invention provides amic acids of itaconic acid and aliphaticprimary and secondary amines having between about 4 carbon atoms andabout 39 carbon atoms per molecule and the amine salts thereof with analiphatic primary amine having between about 4 carbon atoms and aboutcarbon atoms per molecule; and distillate fuel oil containing a minoramount of them, sufiicient to inhibit sedimentation and screen cloggingand to prevent rusting of ferrous metal surfaces in contact therewith.

The addition agents contemplated herein are the amic acids of itaconicacid with aliphatic primary and secondary amines having beteween about 4and about 30 carbon atoms per molecule; and their amine salts withaliphatic primary amines having between about 4 and about 30 carbonatoms per molecule. The amic acids are produced by reacting itaconicacid with the amine reactant in a molar ratio of 1:1, at a temperaturevarying between about C. and about C. from 2 to 5 hours. The reaction isaccompanied by the elimination of water to form amide groups. Thus, itis preferable to carry out the condensation reaction using an azeotropeto remove the Water, such as benzene, toluene, Xylene, etc. The salt ofthe amic acid can be made readily by warming equimolar quantities of theamic acid and an aliphatic primary amine having between about 4 andabout 30 carbon atoms per molecule. The salt-forming amine can be thesame amine used in making the amic acid, or it can be a different amine.In the case where the salt-forming amine is the same used in the amicacid, the salt can be made by heating two moles of amine with one moleof acid under temperatures whereby one mole of water is evolved.

The itaconic amic acids can have the structural formulae:

wherein R is an aliphatic hydrocarbon radical having between about 4 andabout 30 carbon atoms. Indeed, in the aforedescribed condensationreaction, mixtures of both formulae can be produced. For this reason,and because the amines are often mixtures of amines, the amic acids ofthis invention are more accurately defined by their method ofmanufacture.

The amines utilizable in forming the amic acids and the salts thereofare the primary and secondary aliphatic amines having between about 4and about 30 carbon atoms per molecule. These are the monoamines havinga single open chain hydrocarbon group attached to a nitrogen atom. Thealiphatic radical can be saturated or unsaturated, and branched-chain ornormal chain. Likewise mixtures of these amines, as well as pure amines,can be employed. A very useful and readily available class of primaryamines are the tertiary-alkyl, primary, monoamines in which a primaryamino (NH group is attached to a tertiary carbon atom; and mixturesthereof. These amines all contain the terminal group,

Non-limiting examples of the amine reactants are t-butyl amine, n-butylamine, dibutyl amine, t-hexyl primary amine, n-hexylamine, n-octylamine,n-octenylamine, toctyl primary amine, dioctylamine, Z-ethylhexylamine,t-decyl primary amine, n-decylamine, t-dodecyl primary amine,n-undecylamine, dodecenylamine, dodecadienyh amine, tetradecylamine,t-tetradecyl primary amine, t-octadecyl primary amine, dioctadecylamine,hexadecylamine, octadecenylamine, octadecadienyl amine, t-eicosylprimary amine, t-docosyl primary amine, t-tetracosyl primary amine, andt-triacontyl primary amine. The amine reactants can be prepared inseveral ways well known to those skilled in the art. Specific methods ofpreparing the t-allryl primary amines are disclosed in the Journal ofOrganic Chemistry, vol. 20, page 295 et seq. (1955).

Mixtures of such amines can be made from a polyolefin fraction (e.g.,polypropylenes and polybutylene cuts) by first hydrating with sulfuricacid and water to the corresponding alcohol, converting the alcohol toalkyl chloride with dry hydrogen chloride, and finally condensing thechloride with ammonia, under pressure, to produce a t-alkyl'primaryamine mixture.

The fuel oils that are improved in accordance with this invention arehydrocarbon fractions having an initial boiling point of at least about100 F. and an end-boiling point no higher than about 750 F., and boilingsubstantially continuously throughout their distillation range. Suchfuel oils are generally known as distillate fuel oils. It is to. beunderstood, however, that this term is not restrictedv to straight-rundistillate fractions. The distillate fuel oils can be straight-rundistillate fuel oils, catalytically or thermally cracked (includinghydrocracked) distillate fuel oils, or mixtures of straight-rundistillate fuel oils,

naphthas and the like, with cracked distillate stocks. Moreover, suchfuel oils can be treated in accordance with well known commercialmethods, such as, acid or caustic treatment, hydrogenation, solventrefining, clay treatment, etc.

The distillate fuel oils are characterized by their relatively lowviscosities, pour points, and the like. The principal property whichcharacterizes the contemplated hydrocarbons, however, is thedistillation range. As mentioned hereinbefore, this range will liebetween about 100 F. and about 750 F. Obviously, the distillation rangeof each individual fuel oil will cover a narrower boiling range falling,nevertheless, within the above-specified limits. Likewise, each fuel oilwill boil substantially continuously throughout its distillation range.

Particularly contemplated among the fuel oils are Nos. 1, 2, and 3 fueloils used in heating and as diesel fuel oils, and the jet combustionfuels. The domestic fuel oils generally conform to the specificationsset forth in A.S.T.M. Specifications D39648T. Specifications for dieselfuels are defined in A.S.T.M. Specifications D975-48T. Typical jet fuelsare defined in Military Specification MIL-F-5624B.

The amount of itaconic amic acid or amine salt of amic acid additivesthat is added to the distillate fuel oil in accordance with thisinvention will depend, of course, upon the intended purpose and theparticular amic acid or salt selected, as they are not all equivalent intheir activity. Some may have to be used in greater concentrations thanothers to be effective. In most cases, in which. it isdesired to obtainall three beneficial results, namely, to inhibit. sedimentation, toreduce screen clogging, and to prevent rusting of ferrous metalsurfaces,

additive concentrations varying between 10 pounds per thousand barrelsof oil and about 200 pounds per thousand barrels of oil will beemployed. It may not always bedesired, however, to accomplish all threeaforementionedresults. In such cases, where it isdesired to effect onlyone or two results, lower concentrations can be used. Thus, if it isdesired only to prevent rust under dynamic conditions, as in a pipeline,it has been found that concentrations as low as about 5 p.p.m., i.e.,about one pound of additive per thousand barrels of oil, are effective.In general, therefore, the amount. of amic acid or of amine salt of amicacid that can be added to the distillate fuel oil, in order to achieve abeneficial result, will vary generally between about one pound perthousand barrels of oil'and about 200 pounds per thousand barrels ofoil. Preferably, it will vary between about 10 pounds and about 200poundsper thousand barrels of oil.

If it is desired, the fuel oil compositions can contain other additivesfor the purpose of achieving other results.

"Thus, for example, there can be present foam inhibitors and ignitionand burning quality improvers. Examples of such additives are silicones,dinitropropane, amyl nitrate, metal sulfonates, and the like.

The following specific examples are for the purpose of illustrating theamic acids and salts and the fuel oil compositions of this invention,and of exemplifying the specific nature thereof. It is to be strictlyunderstood, however, that this invention is not to be limited by theparticular additives and fuel oils, or to the operations andmanipulations described therein. Other amic acids or amine salts thereofand fuel oils, as discussed hereinbefore, can be used, as those skilledin the art will readily appreciate.

. AMIC ACIDS AND SALTS The amine reactants used in the specific workingexamples are mixtures of pure amines. Amine A is a mixture of primaryamines having a carbon atom ofa tertiary butyl group attached to theamino (NH group and containing 12 to 15 carbon atoms per amine moleculeand averaging 12 carbon atoms per molecule- This mixture contains, byweight, about percent tertiary dodecyl amine, about 10 percent tertiarypenta-' decyl amine, and relatively small amounts, i.e., less than:about 5 percent of amines having less than 12 or more than 15 carbonatoms.

Amine B is a mixture of tertiary-alkyl primary amines averaging 18 to 24carbon atoms per'molecule. it has a tertiary carbon atom attached to the-NH group. It contains, by weight, about 40 percent t-octadecyl primaryamine, about 30 percent t-eicosyl primary amine, about 15 percentt-docosyl primary amine, about 10 percent t-tetracosyl primary amine,and a small amount, less than 5 percent, other amines as high ast-triacontyl primary amine.

Amine C, Amine D, Amine E, Amine F, and Amine G are mixtures or normalaliphatic primary amines having the weight percent compositions setforthin Table I.

Table I Normal Amine Amine Amine Amine Amine Amine C D E F G DodecylTetradecyl Hexadecyl OctadecyL Octadecenyl Octadecadieny EXAMPLE 1 Amixture of 65 grams (0.5 mole) of itaconic acid, gram (0.5 mole) ofAmine A, 100 grams of kerosine having a boiling point range from 343 to519 F., and 50 cc. of benzene was refluxed at 130 C. until the evolutionof water ceased. The amount .of water collected during the reaction was10 cc. (theory 9 cc.). All thebenzene was distilled off. The finalproduct, the Amine A itaconic amic acid, which contained 40% kerosinewas clear and fluid at room temperature.

EXAMPLE 2 A mixture of grams (1 mole) of itaconic acid,

300 grams (1 mole) of Amine B, 200 grams of diluent oil (parafilnic oilof 100 S.U.S. at 100 F.) and 100 cc. of benzene was refluxed at 125 C.until water evolution stopped. The amount of water collected during thereaction was 18 cc. (theory 18 cc.). All the benzene was distilled oil.The final product, the Amine B itaconic amic acid, containing 33%diluent oil, was clear and fluid at room temperature.

EXAMPLE 3 A mixture of 54.2 grams (0.4165 mole) of itaconic acid, 50grams (0.1665 mole) of Amine C, 50 grams (0.25 mole) of Amine A, 100grams of lrerosine (boiling range 343-519 F.) and 70 cc. of benzene wasrefluxed at 117-130 C. until water stopped coming over. The amount ofwater collected during the reaction was 8 cc. (theory 7.5 cc.). All thebenzene was distilled off. The final product, the mixed Amine C-An1ine Aitaconic amic acid, containing 41% kerosine, was clear and fluid at roomtemperature.

EXAMPLE 4:

A mixture of 54.2 grams (0.4165 mole) of itaconic acid, 50 grams (0.1665mole) of Amine D, 50 grams (0.25 mole) of Amine A, 100 grams of xyleneand 75 cc. of benzene was refluxed at 120 C. until water stopped comingover. The amount of water collected during the reaction was 8.5 cc.(theory 7.5 cc.). All the benzene was distilled over. The final product,the mixed Amine D-Aminc A itaconic amic acid, containing 41% xylene wasclear and fluid at room temperature.

EXAMPLE 5 A mixture of 32.5 grams (0.25 mole) of itaconic u acid, 75grams (0.25 mole} of Amine C, 50 grams of xylene and 50 cc. of benzenewas refluxed at 125 C. until water stopped coming over. The amount ofwater collected during the reaction was 4.5 cc. (theory 4.5 cc.). Allthe benzene was distilled off. The final product, the Amine C itaconicamic acid, which contained 33% xylene was clear and fluid at roomtemperature.

EXAMPLE 6 A mixture of 32.5 grams (0.25 mole) of itaconic acid, 32.25grams (0.25 mole) of Amine E, 50 grams xylene and 60 cc. benzene wasrefluxed at 100105 C. until the evolution of water ceased. The amount ofwater collected during the reaction was 4.5 cc. (theory 4.5 cc.). Allthe benzene was distilled oil. The final product, the Amine E itaconicamic acid, which contained 46% xylene was clear and fluid at roomtemperature.

EXAMPLE 7 mixture of 65 grams (0.5 mole) of itaconic acid, 97.5 grams(0.5 mole) of Amine F, 100 grams of xylene and 75 cc. of benzene wasrefluxed at 100 C. until water stopped coming over.

The amount of water collected during the reaction was cc. (theory 9cc.). All the benzene was distilled off. The final product, the Amine Fitaconic amic acid, which contained .0% xlyene was clear and fluid atroom temperature.

EXAMPLE 8 A mixture of 65 grams (0.5 mole) of itaconic acid, 140 grams(0.5 mole) of Amine G, 140 grams of xylene and 75 cc. of benzene wasrefluxed at 115 C. until water stopped coming over. The amount of watercollected during the reaction was 10 cc. (theory 9 cc.). All the benzenedistilled oil. The final product, the Amine G itaconic amic acid, whichcontained 41% xylene was clear and fluid at 50 C. and solidifying atroom temperature.

EXAMPLE 9 A mixture of 43.5 grams /3 mole) of itaconic acid, 150 grams/3 mole) of Amine H, 100 grams of xylene and 75 cc. of benzene wasrefluxed at 125 C. until water stopped coming over. The amount of watercollected during the reaction was 6 cc. (theory 6 cc.). All the benzenewas distilled off. The final product, the Amine H itaconic amic acid,which contained 35% xylene was clear and fluid at room temperature.

EXAMPLE 10 A mixture of 32.5 grams (0.25 mole) of itaconic acid, 50grams (0.25 mole) of Amino A, grams of xylene and 50 cc. of benzene wasrefluxed at 125 C. to form an Amine A itaconic amic acid. Thetemperature was held at 125 C. until water stopped coming over. Theamount of water collected during the reaction was 4.5 cc. (theory 4.5cc.). To the Amine A itaconic amic acid was added at room temperaturewith stirring 75 grams (0.25 mole) of Amine C to form an amine salt. Themixture was stirred at 5 C. for 3 hours. The product, the Amine C saltof Amine A itaconic amic acid, was distilled at C., under a pressure of5 mm. of mercury, until no more benzene and xylene came over.

EXAMPLE 1 1 A mixture of 32.5 grams (0.25 mole) of itaconic acid, 75grams (0.25 mole) of Amine C, 75 grams kerosine (boiling range 343-519F.) and 75 cc. of benzene was refluxed at 135 C. to form an Amine Citaconic amic acid. The temperature was held at 135 C. until waterstopped coming over. The amount of water collected during the reactionwas 6 cc. (theory 4.5 cc.). All the benzene was distilled off. To theAmine C itaconic amic acid was added at room temperature with stirring50 grams (0.25 mole) of Amine A to form an amine salt. The mixture wasstirred at 8590 C. for 3 hours. The final product, the Amine A salt ofAmine C itaconic amic acid, winch contained 33% kerosine was clear andfluid at room temperature.

EXAMPLE 12 A mixture of 65 grains (0.5 mole) of itaconic acid, 149 grams(0.5 mole) of Amine D, grams of xylene and 75 cc. of benzene wasrefluxed at C. to form an Amine D itaconic amic acid. The temperaturewas held at C. until water stopped coming over. The amount of watercollected during the reaction was 9 cc. (theory 9 cc.). All the benzenewas distilled off. To the Amine D itaconic amic acid was added at roomtemperature with stirring 100 grams (0.5 mole) of Amine A to form anamine salt. The mixture was stirred at 75 C. for 2 hours. The finalproduct, the Amine A salt of Amine D itaconic amic acid, which contained25% xylene was clear and fluid at room temperature.

EXAMPLE ,13

A mixture of 65 grams (0.5 mole) of itaconic acid, 68 grams (0.5 mole)of Amine E, 100 grams of xylene and 75 cc. of benzene was refluxed at115 C. to form an Amine E itacc-nic amic acid. The temperature was heldat 115 C. until water stopped coming over. The amount of water collectedduring the reaction was 9 cc. (theory 9 cc.). All the benzene wasdistilled oil". To the Amine E itaconic amic acid was added at roomtemperature with stirring 100 grams (0.5 mole) of Amine A to form anamine salt. The mixture was stirred at 75 C. for 2 hours. The finalproduct, the Amine A salt of Amine E itaconic amic acid, which contained31% xylene was clear and fluid at room temperature.

EXAMPLE 14 A mixture of 65 grams (0.5 mole) of itaconic acid, 97.5 grams(0.5 mole) of Amine F, 100 grams of xylene and 50 cc. of benzene wasrefluxed at 115 C. to form an Amine F itaconic amic acid. Thetemperature was held at 115 C. until water stopped coming over. Theamount of water collected during the reaction was 9 cc. (theory 9 cc.).All the benzene was distilled off. To the Amine F itaconic amic acid wasadded at room temperature with stirring 100 grams (0.5 mole) of Amine Ato form an amine salt. The mixture was stirred at 75 C. for 2 hours. Thefinal product, the Amine A salt of Amine G itaconic amic acid, whichcontained 29% xylene was clear and fluid at room temperature.

EXAMPLE 15 A mixture of 65 grams (0.5 mole) of itaconic acid, grams (0.5mole) of Amine C, 100 grams of xylene and F! Z 50 cc. of benzene wasrefluxed at 125 C. to form an Amine G itaconic amic acid. Thetemperature was held at 125 C. until water stopped coming over. Theamount of water collected during the reaction was 9 cc. (theory 9 cc.).All the benzene was distilled off. To theArnine G itaconic amic acid wasadded at room temperature with stirring 100 grams (0.5 mole) of Amine Ato form an amine salt. The mixture was stirred at 75 C. for 2 hours. Thefinal product, the Amine A salt of Amine G itaconic amic acid, whichcontained 26% xylene was clear and fluid at room temperature.

EXAMPLE 16 A mixture of 43.3 grams /a mole) of itac'onic acid, 66.7grams /3 mole) ofAmine A, 204 grams of diluent oil (paraflinic oil of100 S.U.S. at 100 F.) and 75 ccof benzene was refluxed at 125 C. to forman Amine A itaconic amic acid. The temperature was held at 125 C. untilwater stopped coming over. The amount of water collected during thereaction was 6 cc. (theory 6 co}. All the benzene. was distilled off. Tothe Amine A itaconic amic acid was added at room temperature withstirring 100 grams /3 mole) of Amine B to form an amine salt. Themixture was stirred at 85-95" C. for 3 hours. The final product, theAmine B salt of Amine A itaconic amic: acid, which contained 50% diluentoil was clear and fluid at room temperature.

SEDIMENTATION The test used to determine the sedimentationcharacteristics of the fuel oils is the 110 F. Storage Test. In thistest, a 500-milliliter sample of the fuel oil under test is placed in aconvected oven maintained at 110 F. for a. period of 12 Weeks. Then, thesample is removed from the oven and cooled. The cooled sample isfiltered. through a tared asbestos filter (Gooch crucible) to removeinsoluble matter. The weight of such matter in milligrams is reported asthe amount of sediment. A sample of the blank, uninhibited oil is runalong with a fuel oil blend under test. The effectiveness of a fuel oilcontaining an inhibitor is determined by comparing the weight ofsediment formed in the inhibited oil with that formed in the uninhibitedoil.

The additives described in the examples were blended in test fuel oiland the blends were subjected to the 110 F. Storage Test. The testresults comparing the blended fuels and uninhibited fuels are set forthin Table II. The test fuel oil was a blend of 60 percent distillatestock obtained from continuous catalytic cracking and 40 percentstraight-run distillate stock. It has a boiling range of be tween about320 F. and about 640 F. and is a typical No. 2 fuel oil. 7

Table II [110 F. Storage Test-12 weeks] 6 hours.

8 SCREEN CLOGGING The anti-screen clogging characteristics of a fuel oilwere determined as follows: The test is conducted using a isundstrand V3or S1 home fuel oil burner pump with a self-contained 100-mesh monelmetal screen. About 0.05 percent, by weight, of naturally-formed fueloil :sediment, composed of fuel oil, water, dirt, rust, and or- .ganicsludge is mixed with 10 liters of the fuel oil. This .mixture iscirculated by the pump through the screen for Then, the sludge depositon the screen is washed off with normal pentane and filtered through atimed Gooch crucible. After drying, the material in Gooch crucible iswashed with a 50 (volume) acetone-methanol mixture. The total organicsediment is obtained by evaporating the pentane and the acetone-:methanol filtrates." Drying and weighing the Gooch crucible yields theamount of inorganic sediment. The sum of the organic and inorganicdeposits on the screen can be reported in milligrams recovered orconverted mto percent screen clogging.

' Blends of the additives of the examples were prepared an theraforedescribed test fuel oil and subjected to the Screen Clogging Test.Results are set forth in Table III.

T able III [Screen clogging] Concn, Screen Additive of Example lbs/1,000Clogging,

, bbls. Percent Blank 100 l- 100 32 2- 25 2 3- 50 14 4- 50 3 5- 50 6 6100 9 7- 50 13 8. 50 2 9 25 8 10. 100 5 l1 25 10 RUSTING The method usedfor testing anti-rust properties of the fuel oils was the A.S.T.M. RustTest D665 operated for 48 hours at 80 F. using distilled water. This isa dynamic test that indicates the ability to prevent rusting of ferrousmetal surfaces in pipelines, tubes, etc.

Blends of the additives described in the examples in the aforedescribedtest fuel oil were subjected to the A.S.T.M. gust Test D-665. Pertinentdata are set forth in Table Additive of Example Ooncn, lbs. SedimentTable IV /1,000 bbls. nag/liter [A.S.T.M. Rust; Test D-665] Blank 10Conen Rust Test 25 6 Additive of Example parts per Result Blank 25 V 3million 1 B1 1 1 t F il. Blank 49 1. 2. 5 P385. 5O 37 2 50 Pass. Blank 53. 10 Pass. 25 2 4 10 Pass. 25 2 5 2.5 Pass. Blank a4 6. 50 Pass. 24 7 5Pass. Blank 49 8.- 5 Pass. 1 100 10 9-"- 50 Pass. Blank 141 10. 50 Pass.100 49 11- 2. 5 Pass. Blank 6 12- 10 Pass. 2 50 2 7 13 10 Pass. Blank"34. 14. 5 Pass. 13 50 8 15- 10 Pass. Blank 6 16- 25 Pass. 4 50 1 15 5 116. 25 3 The Static Rust Test simulates conditions encountered 7 instorage tanks, such as, the home fuel Oll storage tank.

In this test, a strip of 16-20 gauge sand blasted steel plate is placedin a cl ar quart bottle. The length of the strip is sufiicient to reachfrom the bottom of the bottle into the neck of the bottle withoutinterfering with the cap. One hundred cc. of synthetic sea Water with pHadjusted to 5 (A.S.T.M. D665) and 750 cc. of test oil are placed in thebottle. The bottle is capped tightly, shaken vigorously for one minute,and permitted to stand quietly at 80 F. for 21 days. At the end of thattime, the amount of rust that occurs on the surface of the plateimmersed in the water is used as a measure of efiectiveness of the fuelto inhibit rushing in storage vessels. It is generally preferred that nomore than 5 percent of the surface should be rusted. This test is muchmore severe than the A.S.T.M. Rust Test. Many additive compositions thatpass the A.S.T.M. test fail in the static test. On the other handmaterials that pass the static test always pass the A.S.T.M. test.

Blends of the additives of the examples in the aforedescribed test fueloil were subjected to the Static Rust Test. Pertinent results are setforth in Table V.

Table V [Static rust test] Gone-n, Percent Additive 01 Example lbs/1,000rusting bbls.

Blank 100 1 35 2 50 30 3-- 50 0 25 u 5 25 0 7 25 0 a 50 0 q 50 10 10 5011 10 0 19 50 1 1 1 so 50 16 75 0 It will be apparent, from the data setforth in Tables 11 through V, that the amic acids of this invention andamine salts thereof are highly etfective to reduce sedimentation andscreen clogging and to inhibit rusting of ferrous metal surfaces. As isto be expected results will vary among specific materials used. In orderto accomplish any given improvement, many of the additives can be usedin relatively small amounts, as for dynamic rust prevention. If, on theother hand, it is desired to accomplish all the aforementionedbeneficial results, this can be accomplished at the practical additiveconcentration of 50400 pounds per thousand barrels of fuel oil.

The present application is a division of copending application, SerialNo. 765,296, filed October 6, 1958, now US. Patent No. 3,046,102.

Although the present invention has been described with preferredembodiments, it is to be understood that modifications and variationsmay be resorted to, without departing from the spirit and scope of thisinvention, as

1% those skilled in the art will readily understand. Such variations andmodifications are considered to be within the purview and scope of theappended claims.

What is claimed is:

1. A material selected from the group consisting of amic acid productsobtained by reacting (A) itaconic acid with primary alkyl amines havinga tertiary carbon atom attached to the amino group and containing fromabout 4 to about 30 carbon atoms per molecule, and (B) salts obtained byreacting A with aliphatic hydrocarbyl amines having from about 4 toabout 30 carbon atoms per molecule.

2. Amie acid products obtained by reacting itaconic acid with primaryallryl amines having a tertiary carbon atom attached to the amino groupand containing from about 4 to about 30 carbon atoms per molecule.

3. Salts obtained by reacting the amic acid products of itaconic acidand primary alkyl amines having a tertiary carbon atom attached to theamino group and containing from about 4 to about 30 carbon atoms permolecule, with aliphatic hydroearbyl amines having from about 4 to about30 carbon atoms per molecule.

4. Arnie acid products obtained by reacting an itaconic acid with amixture of primary alkyl amines having a tertiary carbon atom attachedto the amino group and containing from about 12 to about 15 carbon atomsper molecule and averaging about 12 carbon atoms per molecule.

5. Salts obtained by reacting the amic acid products of itaconic acidand a mixture of primary allryl amines having a tertiary carbon atomattached to the amino group and containing from about 12 to about 15carbon atoms per molecule and averaging about 12 carbon atoms permolecule, with a mixture of primary alkyl amines having a tertiarycarbon atom attached to the amino group and containing from about 12 toabout 15 carbon atoms per molecule and averaging 12 carbon atoms permolecule.

References Eited in the file of this patent UNITED STATES PATENTS2,604,449 Bryant et al July 22, 1952 2,718,503 Rocchini Sept. 20, 19552,879,253 Coover Mar. 24, 1959 2,908,711 Halter et a1 Oct. 13, 19592,944,969 Stromberg et a1. June 12, 1960 2,976,216 De Mytt Mar. 21, 19613,031,282 Andress et a1. Apr. 24, 1962 FOREIGN PATENTS 859,304 GermanyDec. 11, 1952 449,081 Great Britain June 10, 1936 OTHER REFERENCESHolmberg et al.: Chem. Abst, vol. 35, 1941, column Rohm and HaasCompany, TertiaryAlky1 Primary Amines, October 1956, pages 3, 17-21.

UNITED STATES PATENT OFFICE CERTIFICATE OF (ZORRECTION Patent No.3,173,945 March 16, 1965 Harry J, Andress, Jr. et. al.

It is hereby certified that error appears in-the above numbered patentreqiiring correction and that the said Letters Patent should read asoorreotedbelow.

Column 1, line 12, after "containing" insert additives adapted toinhibit the appearance of sediment column 4, line 33, for "or" read ofcolumn 5, line 51, for "100 Cu" read 110 C. column 6, line 75, for"Amine C" read "Amine G Signed and sealed this 24th day of August 1965;

SEAL) nest: IRNEST W. SWIDER EDWARD J. BRENNER nesting OfficerCommissioner of Patents

1. A MATERIAL SELECTED FROM THE GROUP CONSISTING OF AMIC ACID PRODUCTSOBTAINED BY REACTING (A) ITACONIC ACID WITH PRIMARY ALKYL AMINES HAVINGA TERTIARY CARBON ATOM ATTACHED TO THE AMINO GROUP AND CONTAINING FROMABOUT 4 TO ABOUT 30 CARBON ATOMS PER MOLECULE, AND (B) SALTS OBTAINED BYREACTING A WITH ALIPHATIC HYDROCARBYL AMINES HAVING FROM ABOUT 4 TOABOUT 30 CARBON ATOMS PER MOLECULE.